luvdunhill said:
I think if the voltage or current is within 5% is very good, 10% should not have any issue. The total power will be shared among the 3 mosfets. For performance I have no idea. I think a distortion meter or FFT analyzer is needed to see if any differences in harmonics content.
the 6moons F5 review has a little contrast if I am remembering correctly. It's pretty cheap (relatively) to build a single power supply and F4/F5 channels and have both.
Chris
Chris
sry i forgot to ask.
actualy what size of transformer we need to build F4?.
is 300va enough for 2 chnl?
actualy what size of transformer we need to build F4?.
is 300va enough for 2 chnl?
bakpaosiomay said:
generally - anticlick ( delay circ ) and spk protection is welcome addition to any amp which is not containing output xformer or output cap .
but - it's not necessary
bakpaosiomay said:
say that 300VA is lowest value you can use , and still sleep well .....
for the FET can i use 2sk246/2sj103 insteed 2sk370/2sj108?
because in my place very hard to find those type FET.
thanks
because in my place very hard to find those type FET.
thanks
bakpaosiomay said:
nope - if you make amp properly 😉
bakpaosiomay said:
well ..... think of paralleling at least 3 of each , to replace original ones ;
is it possible for you to buy anything outside your country ?
that amp deserves that trouble , believe me .
any Papa's amp worths at least quadruple money , looking at price of his commercial products vs. other competitors .
If you have a source which can drive 5 Kohm and a couple hundred pF,
you can dispense with the JFETs altogether and simply drive the Gates
of the Mosfets.
A little more work, and you can use a single pair of Mosfets and raise
the impedances of the bias circuit, and then it would be about 22K and 70 pF.
😎
you can dispense with the JFETs altogether and simply drive the Gates
of the Mosfets.
A little more work, and you can use a single pair of Mosfets and raise
the impedances of the bias circuit, and then it would be about 22K and 70 pF.
😎
Nelson Pass said:
it is okay to dispense the jfet?.
it will not affect the sound?
if the quality of sound is decrease i will consider to buy those jfet in another country.
thanks
Zen Mod said:
okay i think i will purchase those j-fet overseas.
what do you think about f5 and f4.
what is the main difference?.
i realy confuse.
what is the strength and weakness?
thanks.
bakpaosiomay said:
Main differences:
F4 has no gain
F5 has less power fets
Both are push pull, which is a good thing if this matches your speakers and you like the sound (I do).
bakpaosiomay said:
F4 makes more heat!
I am going back to F4 from F5 -- now that I have an Impasse preamp!
What surprised me about the F4 is how much difference the preamp made. Just put my Pumpkin on them and they are a new animal. They probably are more neutral then most amps and more revealing of the other components. In any case have half the parts for an Impasse gathered it should be interesting the one I will prefer.
Bill
Bill